thdq.hpp

// Copyright (c) 2014-2023, Epic Cash and fireice-uk
// 
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
// 
// 1. Redistributions of source code must retain the above copyright notice, this list of
//    conditions and the following disclaimer.
// 
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
//    of conditions and the following disclaimer in the documentation and/or other
//    materials provided with the distribution.
// 
// 3. Neither the name of the copyright holder nor the names of its contributors may be
//    used to endorse or promote products derived from this software without specific
//    prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#pragma once

#include <condition_variable>
#include <mutex>
#include <queue>
#include <thread>
#include <vector>

template <typename T>
class thdq
{
public:
	T pop()
	{
		std::unique_lock<std::mutex> mlock(mutex_);
		while(queue_.empty())
		{
			cond_.wait(mlock);
		}
		auto item = std::move(queue_.front());
		queue_.pop();
		return item;
	}

	void pop(T& item)
	{
		std::unique_lock<std::mutex> mlock(mutex_);
		while(queue_.empty())
		{
			cond_.wait(mlock);
		}
		item = queue_.front();
		queue_.pop();
	}

	void push(const T& item)
	{
		std::unique_lock<std::mutex> mlock(mutex_);
		queue_.push(item);
		mlock.unlock();
		cond_.notify_one();
	}

	void push(T&& item)
	{
		std::unique_lock<std::mutex> mlock(mutex_);
		queue_.push(std::move(item));
		mlock.unlock();
		cond_.notify_one();
	}

private:
	std::queue<T> queue_;
	std::mutex mutex_;
	std::condition_variable cond_;
};

template <typename T>
class thdv
{
public:
	thdv() { vector_.reserve(1024); }

	void pop_all(std::vector<T>& out)
	{
		out.clear();
		std::unique_lock<std::mutex> mlock(mutex_);
		cond_.wait(mlock, [this] { return !vector_.empty(); });
		vector_.swap(out);
		vector_.reserve(1024);
		mlock.unlock();
	}

	template <class... Args>
	void emplace(Args&&... args)
	{
		std::unique_lock<std::mutex> mlock(mutex_);
		vector_.emplace_back(args...);
		mlock.unlock();
		cond_.notify_one();
	}

private:
	std::vector<T> vector_;
	std::mutex mutex_;
	std::condition_variable cond_;
};